In the normal case, packages are to be relocated from one place of production to a further production line. At the individual production places, the delivery point or the receiving point for the packages is not always located on one and the same level. As the case may be, it is also necessary to bridge entire stories of a building.
Transportation means which receive packages or bobbins are often of a different design and construction. Thus, it is possible to move the packages by means of a conveyor belt in the region of the one production place, whereas in the region of the next production place, it becomes necessary to transfer the same package, for example, to an overhead conveyor, to be further transported by the latter.
To bridge differences of height, use is made of so-called package lifters or package elevating mechanisms, such as are disclosed, for example in the German Patent 33 34 977 and German published Application OS 37 12 378, which also correspond to a device as defined in the preamble of the claim.
In the case of the package transport device disclosed in German OS 37 12 378, the actual package carrier comprises two parallel, spaced-apart roller trains, which advance the packages supported thereon by the action of gravity. The vertical axis, about which the actual package carrier can be rotated, is laterally located outside the actual package carrier. As a result the device requires a relatively large space in the horizontal direction.
The package transport device disclosed in German Patent 33 34 977 comprises a lifting mechanism in the form of a lifting column arranged substantially centric with the package carrier, which cooperates during its upward and downward movements with a lateral cam guide, so as to be able to rotate the lifting mechanism and thus the package carrier. The rotation of the package carrier therefore depends on a certain height position and the design and construction of the cam guide, so that as a result relatively narrow limits are set. The actual package supporting means consists of lateral carrying and supporting arms. In the region of the receiving point for packages, a conveyor in the form of driven belts is associated to the package transport system. These belts are operative exclusively in the region of the package receiving point. For the transfer of the packages from the transport device after having being moved upward, special receiving units are necessary, for example, in the form of mandrills or pins, which are adapted to enter into the tubes of the packages and arranged on an overhead conveyor. This known device does not permit, or makes it almost impossible, to convey the packages, for example, from a higher level to the region of a lower level, since the arrival of packages at a higher level does not ensure a reliable transfer of the package to the package transport device.
Further, both known package transport devices do not have the possibility of receiving the packages by the transport device safely from both sides of the transport device, since the two package transport devices are equipped with stops, which permit to receive packages at the receiving point only from one side.